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Abstract Bis‐porphyrin nanocages (M2BiCage, M = FeCl, Co, Zn) and their host‐guest complexes with C60and C70were used to examine how molecular porosity and interactions with carbon nanomaterials affect the CO2reduction activity of metalloporphyrin electrocatalysts. The cages were found to adsorb on carbon black to provide electrocatalytic inks with excellent accessibilities of the metal sites (≈50%) even at high metal loadings (2500 nmol cm−2), enabling good activity for reducing CO2to CO. A complex of C70bound inside(FeCl)2BiCageachieves high current densities for CO formation at low overpotentials (|jCO| >7 mA cm−2,η= 320 mV; >13.5 mA cm−2,η= 520 mV) with ≥95% Faradaic efficiency (FECO), andCo2BiCageachieves high turnover frequencies (≈1300 h−1,η= 520 mV) with 90% FECO. In general, blocking the pore with C60or C70improves the catalytic performance of(FeCl)2BiCageand has only small effects onCo2BiCage, indicating that the good catalytic properties of the cages cannot be attributed to their internal pores. Neither enhanced electron transfer rates nor metal‐fullerene interactions appear to underlie the ability of C60/C70to improve the performance of(FeCl)2BiCage, in contrast to effects often proposed for other carbon nanosupports.
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This content will become publicly available on April 29, 2027
Fourier imaging of diffraction in elastic e -C 60 scattering: effects of impact energy and high angular momentum
Abstract Our recent study Aiswarya (2024Phys. Rev. Lett.133033002) accessed the angle-energy two-dimensional diffraction in elastic electron scattering from C60with implications for ultrafast electron diffraction studies. The objective of the current investigation is to carry out a detailed characterization of the Fourier transformed signals of diffraction fringes in the angular distribution for a range of impact energies. Results shed light on how the electron’s perception of the molecular target evolves as a function of its de Broglie wavelength and tends to be geometrically accurate at faster impacts. For very fast impacts and the resulting dominance of high angular momentum partial waves, the target becomes partly hidden within a spherical shell of repulsive centrifugal barrier, from which the electron ‘self-diffracts’. This effect is favored by the polarization interaction of C60. Potentials from a jellium-based density functional theory within the local density approximation and an annular square well model are independently applied to simulate the C60environment. Results from the partial wave analysis and Born approximation are independently analyzed by a fast Fourier transformation technique.
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- PAR ID:
- 10696617
- Publisher / Repository:
- Institute of Physics Publishing
- Date Published:
- Journal Name:
- Journal of Physics B: Atomic, Molecular and Optical Physics
- Volume:
- 59
- Issue:
- 9
- ISSN:
- 0953-4075
- Page Range / eLocation ID:
- 095201
- Subject(s) / Keyword(s):
- electron scattering, elastic collision, polarization, diffraction
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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